Let A, B, C, D and E be such that A,B and C are in A.P ; B,C and D are in G.P; and C, D and E are in H.P; then A,C and E are in
If sin (B + C − A), sin (C + A − B), sin (A + B − C) are in A.P., then cot A, cot B and cot C are in (a) GP (b) HP (c) AP (d) None of these